The young actress goes beyond the pale in a revolutionary new computer game, writes Ronan Price

"It was the most difficult acting job I've ever had," says Ellen Page. "The concept is huge and there are incredible action sequences, locations all over the world but there's also this beautiful drama within."

"It was the most difficult acting job I've ever had," says Ellen Page. "The concept is huge and there are incredible action sequences, locations all over the world but there's also this beautiful drama within."

The 26-year-old Canadian actress talks excitedly about her latest project, lapsing occasionally into luvvie speak – "incredibly challenging," "fulfilling experience" – but there's no doubting her enthusiasm and sincerity. Thing is, she's not discussing a new movie or become the latest Hollywood star to cross over into a big-hitting TV series.

Instead, Page has spent months in a mostly empty room making a videogame with craggy-faced thespian Willem Dafoe called Beyond: Two Souls. Their wardrobe consisted of nothing more than black catsuits covered in tiny grey balls. Their props were frequently just lumps of wood or metal.

"It was strange because it felt so foreign to me," admits Page of the set-up in the motion-capture studio. "It sort of felt like jumping off a cliff a little bit. Maybe that's what I did, jumped, I guess."

Frankly, it was not a good look for an Oscar-nominated actress – even her face was dotted every day of the shoot with the grey balls – but the effort was worth it because she humanises the most extraordinary game of 2013.

Beyond eschews the tattered videogame tropes of big guns, over-muscled soldiers and improbably proportioned women. Instead, it mines a rare seam of introspective, interactive storytelling, spanning a decade of the life of a young woman cursed with a supernatural guardian.

Page's subtle performance – masterfully motion-captured and conveyed on-screen with unnervingly realistic graphics – is equally at home channelling the eight-year-old girl as it is her older teenage version. Dafoe comfortably holds his own in a supporting role as a CIA agent assigned to investigate her.

While the actress anchors the emotional centre, the narrative is driven by Beyond's director David Cage, a French auteur with a history of left-of-centre story-led games.

"I want to create an emotional journey, a unique experience," Cage told Edge magazine during the game's protracted development. "I am not interested in giving people 'fun', I want to give them meaning; I don't want to challenge their thumbs, I want to challenge their minds."

True to his word, Beyond is no twitchy shoot-em-up. The player gently guides the characters through the scenes – there is no failure, no game over. The branching storyline caters for all eventualities – if you fluff a task, the game moves on.

Make no mistake, though, Beyond delves into some dark places, going where few of its peers dare – sexual assault, drug use, homelessness, euthanasia. Amid the many grim but moving moments lie glimpses of light, such as the home-birth and the awkward first date.

All of this is made possible by Cage's 2,000-page shooting script and the bare Paris-based sound-stage where it was all brought to life.

"You walk past the performance capture space and it looks so tiny and so simple," explains Dafoe. "You look at that and say, My God, all that stuff, happened in that space today. When I say happened I mean in your imagination. It's a powerful feeling."

Cage believes what he and his team did is unique. "What we used to do in the past was to shoot the voice in a sound booth. You lost all the body expression, all the subtleties. For Beyond it was completely different."

Critics have responded to Beyond with accusations it lacks player involvement. But with dozens of possible endings, Cage is asking you to find meaning in your choices. Try that playing Call of Duty.